Robin van Persie faces a possible three-game suspension for violent conduct after appearing to elbow Yohan Cabaye in an incident apparently unseen by the referee, Howard Webb, during his side's 3-0 win at Newcastle United on Sunday.

If Webb's official report confirms he did not spot the altercation then the Football Association can use video evidence to take retrospective action against the Manchester United striker and a ban may beckon.

Van Persie, who had earlier been booked, looked to catch the Newcastle midfielder late in the game when occupying space that served as Webb's blindspot.

"There's a bit of history between those two players and I don't know whether he's got caught up in that but it was a little bit unsavoury.

"At the time I didn't see it [the elbow] but I thought Yohan wouldn't have gone down if Van Persie hadn't done something. But I've obviously seen the replay now and it looks as if Van Persie's looked at him and put the elbow in. But that's for the FA to decide on, not me. I'm not going to take anything away from Manchester United though. They deserved to win. They came and played very, very well in periods. Wayne Rooney was terrific, a class act."

Newcastle's manager was frustrated that his side, who recovered well from two early set-piece concessions, did not celebrate a goal early in the second half when Papiss Cissé's header was ruled not to have crossed the line. "You're talking inches and even after looking at it three or four times on video you're still not sure if it's all in or it's just stayed out," Pardew said. "It's very, very close and you'd like to have that conclusive picture.

"I genuinely think if we'd got a goal at 2-0 down then suddenly the stadium would have come alive and the way we are and the spirit we've got in the group, we could have got something from it."

Rooney agreed the game was harsher than the scoreline suggested. "It's a huge result," he said. "Newcastle away is one of the hardest games of the season. Certainly the first six games of the season, we haven't defended well enough. That isn't just the back four, that's the whole team. Today we were brilliant. There was a focus about us and we need to continue to do that for the rest of the season if we are going to be successful."

Sir Alex Ferguson believed it was his team's best performance of the season. "We were on top of our game," said Manchester United's manager. There was concentration and determination.

"Some of Wayne Rooney's football was terrific. He likes to work a bit more forward, but we set up the diamond with him in the middle of the pitch. There was a bit of pressure on us after City and Chelsea winning because you don't want to fall too far behind."